NAME

       Bear - Build EAR

SYNOPSIS

       bear [options] [build command]

DESCRIPTION

       Bear is a tool to generate compilation database for clang tooling.

       The  JSON compilation database <http://clang.llvm.org/docs/JSONCompilationDatabase.html> is used in Clang
       project to provide information how a single compilation unit was processed.  When that is available  then
       it is easy to re-run the compilation with different programs.

       Bear  executes the original build command and intercepts the subsequent execution calls.  To achieve that
       Bear uses library preload mechanism provided by the dynamic linker.  There is a library which defines the
       exec methods and used in every child processes of the build command.  The executable itself sets the  en‐
       vironment up to child processes and writes the output file.

OPTIONS

       --version
              Print out Bear version number.

       -v, --verbose
              Enable verbose output from Bear.  A second, third and fourth flags increases verbosity.

       -o file, --cdb file
              Specify  output file.  (Default value provided.) The output is not continuously updated, it's done
              when the build command finished.

       --use-cc program
              Hint Bear to classify the given program name as C compiler.

       --use-c++ program
              Hint Bear to classify the given program name as C++ compiler.

       -a, --append
              Use previously generated output file and append the new entries to it.  This way you can run  Bear
              continuously during work, and it keeps the compilation database up to date.  File deletion and ad‐
              dition  are  both considered.  But build process change (compiler flags change) might cause dupli‐
              cate entries.

       -l path, --libear path
              Specify the preloaded library location.  (Default value provided.)

OUTPUT

       The JSON compilation database definition changed over time.  The current version of  Bear  generates  en‐
       tries where:

       directory
              has absolute path.

       file   has relative path to the directory.

       arguments
              used  instead  of  command to avoid shell escaping problems.  The source file in the compiler call
              match to the file attribute, therefore it is relative path to directory.  Other filesystem related
              references are not modified (those still can be absolute or relative depending the  original  com‐
              mand).

       Some non compilation related flags are filtered out from the final output.

EXIT STATUS

       Bear  exit status is the exit status of the build command.  Except when bear crashes, then it sets to non
       zero.

ENVIRONMENT

       INTERCEPT_BUILD_TARGET_DIR
              Temporary directory to collect the execution reports at one place.  Directory path is derived from
              TMPDIR, TEMP or TMP environment variable.

       LD_PRELOAD
              Used by the dynamic loader on Linux, FreeBSD and other UNIX OS.  Value set by Bear, overrides pre‐
              vious value for child processes.

       DYLD_INSERT_LIBRARIES
              Used by the dynamic loader on OS X.  Value  set  by  Bear,  overrides  previous  value  for  child
              processes.

       DYLD_FORCE_FLAT_NAMESPACE
              Used  by  the  dynamic  loader  on  OS  X.   Value set by bear, overrides previous value for child
              processes.

FILES

       libear.so or libear.dylib
              The preload library which implements the exec methods.

SEE ALSO

       ld.so(8), exec(3)

BUGS

       Because Bear uses LD_PRELOAD or DYLD_INSERT_LIBRARIES environment variables, it does not  append  to  it,
       but  overrides  it.   So  builds which are using these variables might not work.  (I don't know any build
       tool which does that, but please let me know if you do.)

       Security extension/modes on different operating systems might disable library preloads.  This  case  Bear
       behaves normally, but the result compilation database will be empty.  (Please make sure it's not the case
       when reporting bugs.) Notable examples for enabled security modes are: SIP on OS X Captain and SELinux on
       Fedora, CentOS, RHEL.

COPYRIGHT

       Copyright (C) 2012-2017 by László Nagy <https://github.com/rizsotto/Bear>

AUTHORS

       László Nagy.

Bear User Manuals                                April 20, 2017                                          BEAR(1)